The present invention relates to an apparatus for processing the image data input from an image-handing device and then outputting the image data to another image-handling device. The invention also relates to a method of processing image data input from an image-handing device before the image data is output to another image-handling device.
As various systems which handle color images come into use in increasing numbers, it is demanded that color images be reproduced in the same hues by the devices of different types that are used in these systems. To meet this demand, image-processing apparatuses have been proposed, each designed to evaluate the devices for their characteristics and adjust the color values of the image output from the devices to the same value. FIG. 1 shows such an image-processing apparatus. FIG. 2 illustrates the flow of image data in the image-processing apparatus shown in FIG. 1.
Even if the color values of the images output from the devices are adjusted to the same value, however, the colors of the images do not always appear identical to human eyes. This is because the observation environment including ambient light influences the human visual sense. That is to say, the same color looks different in different observation environments.
The devices may differ in terms of the darkest points. (That is, the black part of the image that one device outputs may differ from that of the image that another device outputs.) Particularly in this case, the images output by the devices appear greatly different. Assume that the darkest point of an input device differs from that of an output device. Then, either graying or black-emphasizing occurs in the image output by the output device. Consequently, the input image and the output image may look quite different in terms of color.